When Indian airports are back to a chaotic ambience with resuming the screening and Covid tests for international passengers in the wake of sudden surge of Coronavirus pandemic in China and in several countries, a top health expert of India has come to provide a breather that Indians don't need to panic with the new variant and the government should practice variant and clinical surveillance. 

The new strain 'BF.7', from the Omicron variant, is causing a sharp surge in China and India has reported four cases of BF.7 variant which alarmed to the government to implement the screening at the airports and several state governments have resumed Covid tests and installed additional beds and medical infrastructure at the hospitals. While it has been warned that the variant is highly transmissible and it also can affect those who are vaccinated, Dr Gagandeep Kang, a top Indian microbiologist and researcher has opened up about the jittering situation and whether we need to be worried. 

Kang took to Twitter and opened up about what drove the recent surge of Covid cases. In a series of tweets, she took Indians through some vital information and touched upon various subjects from vaccination to why she is not expecting a surge in India. She wrote, "Let's start with China. China is opening up fast at a time when their population has low levels of exposure to natural infection. The current circulating variants are Omicron, which have evolved in vaccinated populations and are therefore very infectious." 

Reminiscing the massive surge in India during April -May 2021 and January 2022, Dr Kang said that the current situation is similar and China will have more infections. She wrote, "This means that China will have lots & lots of infections. Remember India's 100s or 1000s of cases in April-May 2021 and Jan 2022? In the absence of significant mitigations, this will be similar. Lots of infections lead to lots of sick people." 

"Most of China's population has received 2 doses of vaccines. Most infections can be managed at home, but sheer numbers mean that even a small proportion getting severely ill, means that many people will have severe disease and that a proportion of those will die", she added. By citing that the older age and people with comorbidities will continue to be drivers of severe disease and deaths, she stated that most of China has received two doses of inactivated vaccines and these inactivated vaccines work well to prevent severe disease/death, but somewhat less well than the mRNA/vectored vaccines. 

"So the vaccines will prevent a proportion of severe disease/deaths, but numbers of people needing hospitals and dying will be higher than we have become used to in the past several months", she tweeted and adding that, "When lots get sick, that includes healthcare workers. Understaffed, overloaded hospitals mean poorer care for patients. Also in winter, other viruses/infections result in more hospitalisations (the tripledemic in the rest of the world), making this bad time in hospitals." 

On the question of what does this mean for the rest of the world and what should we be doing, Dr Kang explains, "As far as we know, there are no new variants. China has the capacity to sequence, & we hope it will share data in real time. The variants now circulating in China have been in the rest of the world for months. The behaviour of the virus is not any different from expected." Highlighting about the two variants in India - XBB and BF.7, she said that these variants are very good at infecting people because they escape the immune response that prevents infection, but are not causing more severe disease than delta." 

She further said, "Omicron does result in severe disease in a proportion of infected, but not as severe as delta. It is not mild, but it does infect the upper respiratory tract more than lower. Each new subvariant thrives only if it is better at immune escape than the prior ones. Therefore, greater infectiousness of new variants is a given & not news. Worry with China is not just the tragedy unfolding for them as they undergo what we have already experienced, but that high levels of replication mean increased opportunity for new variants to emerge."

In the front of why should we do to detect the change in the behaviours of the virus, she underlined, "For this, they (China) and we should maintain variant & clinical surveillance to ensure that we detect signal of any changes in the behaviour of the virus. This is a public health function where stable surveillance runs in the background & ramps up for emerging threats." She recommends that periodic serosurveys and environmental surveillance can be useful for such stable surveillance. 

Responding whether India is in high threat, Dr Kang said, "Our population is vaccinated with the primary series, & has had high rates of infection (90% estimated). Most infections were during Omicron, & this gives us hybrid immunity." By affirming that she is not expecting a surge, she wrote, "At the moment, India is doing fine. We have few cases, we have had the XBB & BF.7 for a while and they have not driven an upsurge in India. In the absence of an even more highly infectious variant, I do not expect a surge." 

"But will we be able to detect a new variant or a surge? We have ample sequencing capacity & if sequencing is done in real-time, absolutely we can. When hospitals begin to see severe cases, we will know. Need to & can understand & measure both the virus & the disease. A signal maintained over a couple of weeks is a generally useful construct of the shape of the future. Look at where we are in India. There is no signal at the moment, & we are watchful", she asserted. 

On the question of who needs booster doses, Dr Kang wrote, "Booster doses on any platform are likely to have an incremental benefit in anyone, at least for a while. Among vaccines in India, all vaccines fine, but order based on immune response will be protein, adenovirus vectored, inactivated." By citing that the value of a booster in the elderly population is clear in India than the rest of the world, she advises, "So if you have an elderly person in your family, please get them an additional dose, as a precautionary measure even without any Indian data. May help, unlikely to harm." 

She further said, "For younger. healthier people, the value is likely to be less, but not zero. For public health programmes to be delivered by government, this is a different situation where vaccinating everyone for marginal benefits means that other healthcare will be deprived of resources." She also has left instructions to the general public in adhering to the basic guidelines and responding about wearing masks, she wrote,"I think more important than mandate is an understanding of the purpose & setting for mask use." 

"If you have any respiratory infection, stay home. If you need to go out, go masked. If you are vulnerable, stay masked in unfamiliar company or if someone around you is obviously ill. If there is a lot of infections/cases in the community, staying masked in crowds is good", she added. For the people who are planning to travel, Dr Kang said, "Risk perception again, but no need to stop right now. There is very little infection in India. Travel, wear a mask if you are worried. Outside India, some places have more infections, wear a mask & go travel (not China at the moment)."